Lecture 5 Flashcards
Visual attention (38 cards)
What is visual attention?
The cognitive process of selecting and processing specific visual information while ignoring irrelevant stimuli.
What is overt attention?
Attention that is aligned with eye movements—looking directly at what you’re attending to.
What is covert attention?
Shifting focus to a location or object without moving the eyes.
What is the spotlight metaphor of attention?
Visual attention acts like a spotlight, enhancing perception in a specific spatial region while ignoring others
What is feature search?
A visual search where the target differs by a single feature (e.g., color). It is fast and parallel and unaffected by the number of distractors.
What is conjunction search?
A visual search where the target shares features with distractors, requiring attention to bind features. It is slower and serial
What is Treisman’s Feature Integration Theory (FIT)?
A theory proposing that features are processed separately in a preattentive stage, and are only bound into unified objects in a focused attention stage.
What is the preattentive stage in FIT?
An automatic, parallel stage where individual features (e.g., color, shape) are processed without focused attention.
What is the focused attention stage in FIT?
A serial stage requiring attention to bind features together into coherent objects.
What are illusory conjunctions?
Errors in perception where features from different objects are incorrectly combined, often due to lack of attention.
What is the binding problem?
The challenge of how the brain integrates separate features (like color and shape) into a single perceptual object.
What is space-based attention?
Attention directed to specific locations in space, regardless of the object at that location.
What is object-based attention?
Attention that spreads across an entire object, even to parts not initially cued, showing we select objects, not just locations.
What did Posner’s spatial cueing study show?
That valid cues improve reaction time and invalid cues slow it down, even when participants don’t move their eyes—evidence for covert attention.
What is visual neglect?
A neurological disorder, often from right parietal lobe damage, where patients ignore the left side of space (both perceived and imagined).
Which brain area controls spatial attention and is involved in neglect?
The parietal lobe, particularly in the right hemisphere.
: What are the frontal eye fields (FEF)?
Brain regions that control eye movements and covert attention shifts.
What is the role of the pulvinar in attention?
A thalamic structure that helps regulate and coordinate visual information and attention.
How does attention affect the visual cortex (e.g., V1–V4)?
Attention enhances neural activity in areas corresponding to the attended location or object
What evidence supports object-based attention?
Faster responses to uncued parts of the same object than to equidistant locations on different objects
What is visual imagery?
The ability to form mental visual representations of objects, scenes, or spatial layouts without sensory input.
What did Shepard & Metzler’s (1971) mental rotation study show?
Reaction time increases linearly with the angle of rotation, suggesting people mentally rotate images as if they were real objects.
Which brain area is activated during visual imagery, similar to real perception?
The primary visual cortex (V1) and surrounding visual areas.
What happens in the brain when imagining larger vs. smaller objects?
Larger imagined objects activate more anterior regions of the visual cortex.
